Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

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-Topic 210
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Current Liabilities
-URI http://asc.fasb.org/extlink&oid=6509677

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Schedule I - Dividends from Subsidiaries - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands							12 Months Ended
	Feb. 22, 2016	Jan. 05, 2016	Sep. 16, 2015	Jun. 10, 2015	Mar. 03, 2015	Jan. 05, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Dividends Payable [Line Items]
Dividends payable							$ 430	$ 172	$ 17,939
Cash dividends declared per share			$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.84	$ 0.62	$ 0.60
Cash dividends record date			Sep. 29, 2015	Jun. 22, 2015	Mar. 13, 2015	Jan. 13, 2015
Cash dividends payable date			Oct. 06, 2015	Jul. 01, 2015	Apr. 01, 2015	Jan. 22, 2015
Subsequent Events [Member]
Dividends Payable [Line Items]
Cash dividends declared per share	$ 0.21	$ 0.21
Cash dividends record date	Mar. 14, 2016	Jan. 15, 2016
Cash dividends payable date	Apr. 01, 2016	Jan. 22, 2016
Parent Company [Member]
Dividends Payable [Line Items]
Dividends payable							$ 430	$ 172	$ 17,939
Parent Company [Member] \| Subsequent Events [Member]
Dividends Payable [Line Items]
Dividends payable	$ 18,600
Cash dividends declared per share	$ 0.21	$ 0.21
Cash dividends record date	Mar. 14, 2016	Jan. 15, 2016
Cash dividends payable date	Apr. 01, 2016	Jan. 22, 2016
Parent Company [Member] \| Subsequent Events [Member] \| Maximum [Member]
Dividends Payable [Line Items]
Dividends payable		$ 17,787